A Study On Childhood Leukemia Epidemic Situation And Risk Factors In Tianjin

Leukemia is the most common childhood cancer. Data of the Tianjin Cancer Register was analyzed for epidemic trend of leukemia in children under 20 years of age from 1981 to 2000 in Tianjin. Meanwhile 199 case-control in order to know epidemiology of childhood leukemia and make preventive measures effectively.All childhood leukemia diagnosed in the study was coded according to the ICD-0. Incidence rates, mortality rates and mortality and morbidity ratio were calculated by age and sex over twenty years in Tianjin; By 1:1 case-control study, 199 cases of child leukemia and controls from non-cancer and non-hematologic patients in Tianjin were analyzed with the Cox regression model for knowing the risk factor of childhood leukemia.Result showed: 1. 473 incident cases, 269 males and 204 females included, were collected from 1981 to 2000. The incidence rates of childhood leukemia have not changed since 1981. 2. 239 death cases, 139 males and 100 females included, were collected from 1981 to 2000. The mortality for childhood leukemia decreased slowly period 1981-2000 in Tianjin. 3. Mortality and morbidity ratio was 0.51 and 0.58 among children and adult respectively. So prognosis of childhood leukemia was better than adult. The types of lymphoid, myeloid and single-nucleus cell were the most common childhood leukemia in Tianjin, comprised 37.8%, 33. 8 % and 21. 1% respectively. 4. In the multi-factor regression analysis, there were six indexes with significance (P<0. 05).The suspicious risk factors included frequency of cold, high birth weight, environmental pollution, parental occupational exposures (benzene, chemicals and mineral oil), parental education and drugs during the mother pregnancy.I n word, I n T i anj i n morta I ity from ch i I dhood I eukemi a has decreased over twenty years due to therapeutic improvements. In the future suspicious risk factors should be avoided in order to reduce the incidence of child leukemia.